The Paris Climate Agreement invited countries to develop by 2020 “mid-century, long-term low greenhouse gas emission development strategies.” This Strategy answers that call, laying out a strategy to deeply decarbonize the U.S. economy by 2050.

The mid-century vision described in this report is grounded in decades of research and analysis by the U.S. government. It draws heavily on peer-reviewed academic literature and is informed by a wealth of studies on the decarbonization of energy systems and land sector carbon dynamics.

The Strategy was informed by the input received at a series of stakeholder listening sessions with non-governmental and private sector organizations in the summer of 2016 and by ongoing collaboration with Canada, Mexico, and other nations that are developing mid-century strategies.

The purpose of the Strategy’s analysis is not to predict near-term policy making, model the future U.S. energy and land sectors with precision, or encompass the full range of possible low-GHG pathways, but rather to describe key opportunities and challenges associated with our illustrative pathways, and highlight ndings that are robust across scenarios.

The Strategy scenarios include numerous pathways to an 80 percent reduction below 2005 levels in 2050 (including an “MCS Benchmark” scenario that we use as a basis for discussion and comparison throughout this report), and a “Beyond 80” scenario that shows deeper emissions reductions enabled by the innovation prompted by greater global climate action.

The report said achieving deep economy-wide net greenhouse gas emission reductions will require three major categories of action:

-- Transitioning to a low-carbon energy system, by cutting energy waste, decarbonizing the electricity system and deploying clean electricity and low carbon fuels in the transportation, buildings, and industrial sectors;

-- Sequestering carbon through forests, soils, and CO2 removal technologies, by bolstering the amount of carbon stored and sequestered in U.S. lands (“the land sink”) and deploying CO2 removal technologies like carbon bene cial bioenergy with carbon capture and storage (BECCS),1 which can provide “negative emissions”; and

-- Reducing non-CO2 emissions, such as methane, nitrous oxide, and fluorinated gases, which result mainly from fossil fuel production, agriculture, waste, and refrigerants.

The energy system—including electricity, residential and commercial buildings, industry, and transportation—is responsible for about 80 percent of U.S. GHG emissions. The Strategy envisions deep emission reductions through the following three levers:

-- Cutting energy waste: Energy efficiency improvements enable the energy system to provide the services we need with fewer resources and emissions. Over the past several years, the United States has demonstrated that programs and standards to improve the energy efficiency of buildings, appliances and vehicles can cost-effectively cut carbon pollution and lower energy bills, while maintaining significant support from U.S. industry and consumers. Technological advancements will further expand the opportunities for cost-effective energy efficiency improvements. “Smart growth” strategies can also reduce the country’s structural energy needs, for example, through improved urban design that supports alternative transit options. In the Strategy Benchmark scenario, primary energy use declines by over 20 percent between 2005 and 2050.

-- Decarbonizing the electricity system: By 2050, nearly all fossil fuel electricity production can be replaced by low carbon technologies, including renewables, nuclear, and fossil fuels or bioenergy combined with carbon capture, utilization and storage (CCUS). Current electricity grids can handle near-term rapid expansion of variable energy sources like solar and wind, and with additional exibility through, for example, demand response, electricity storage, and transmission improvements, variable renewables have the potential to provide the majority of electricity by mid-century. The corresponding electricity generation mix in 2050 includes significant contributions from renewables (55 percent), nuclear (17 percent), and fossil fuels with CCUS (20 percent). While public policies will help to achieve this mix, existing market trends toward lower cost clean electricity will also play a critical role.

-- Shifting to clean electricity and low-carbon fuels in transportation, buildings, and industry: The vast majority of energy for transportation is currently provided by petroleum, while the industry and buildings sectors are powered by a mix of fuels including natural gas, coal, petroleum, and electricity.

With a clean electricity system comes opportunities to reduce fossil fuel usage in these sectors: for example, electric vehicles displace petroleum use and electric heat pumps avoid the use of natural gas and oil for space and water heating in buildings.

Other low-carbon fuels like hydrogen and carbon-beneficial forms of biomass will also play an important role, particularly for energy uses that are difficult to electrify, such as aviation, long-haul trucking, and heat production in certain industrial sectors.

In the Strategy Benchmark scenario, direct fossil fuel use, i.e., not including electricity generated using fossil fuels, decreases by 58 percent, 55 percent, and 63 percent in buildings, industry, and transportation, respectively, from 2005 to 2050.

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About Me

This Blog is a companion to www.PaEnvironmentDigest.com, the weekly online newsletter published by Crisci Associates, Harrisburg, PA.
I can be contacted at 717-576-0420 or by sending email to: DHess@CrisciAssociates.com.
I served as Secretary of the Pennsylvania Department of Environmental Protection from 2001 to 2003, Executive Deputy at DEP from 1995 to 2001, as staff to the PA Senate Environmental Committee and various positions in the former Department of Environmental Resources, working on environmental issues for nearly 40 years.